Astronomers’ have discovered a moon-sized zombie star that could change the way they understand how stars evolve. This cindering core of a dead star — or white dwarf — is roughly the size of Earth’s moon, qualifying it as the smallest one discovered, according to an article published on Live Science on July 2, 2021.
Despite the zombie star being labeled as tiny, it has a radius of 2,670 miles — compared to the sun’s 432,470-mile radius — and has a mass equalling around 1.35 times that of the sun.
The white dwarf is nicknamed ZTF J190132.9+145808.7 and is located around 130 light-years away from Earth. Due to its fast rotation, it can make a full revolution every 6.9 minutes. To scientists’ astonishment, this zombie star has a magnetic field up to 1 billion times stronger than Earth’s at its surface. Another example of the star’s strong magnetic field is it is 900 times the strength of the sun’s.
Interestingly enough experts believe that the dense, smoldering white dwarf is shrinking. This could mean one of two things:
- The zombie star is about to explode;
- Or the star is about to transform into a neutron star — which is usually created by a supernova.
According to a research associate in theoretical astrophysics at Caltech and lead author of a new study that describes the star, Ilaria Caiazzo, they have “caught this very interesting object that wasn’t quite massive enough to explode.” Scientists are currently “probing how massive a white dwarf can be.”
A zombie star is created when the fusion process in the core center stops when the helium has been converted to carbon. The contacting carbon core ceases to reach temperatures high enough to ignite. Then the electrons are squeezed into the smallest space possible.
Next, the zombie star starts to have quantum mechanical issues causing the gravity to stop. Once the core stops contracting, the star’s temperature rises above 100,000 Kelvin and illuminates through residual heat.
A study published in the journal Publications of the Astronomical Society of the Pacific, 97 percent of the stars in the Milky Way is destined to become a white dwarfs.
Neutron stars are denser than zombie stars. In fact, they are so dense that they get their name from their powerful gravitational fields.
Scientists believe the zombie star has an unusually high mass due to a Frankenstein-like union between two smaller white dwarfs.
Caiazzo’s team published their findings of the Frankenstein-like zombie star on June 30th in the journal Nature.
Written by Sheena Robertson
Sources:
Live Science: Frankenstein star could be on the brink of a startling transformation; by Ben Turner
COSMOS – The SAO Encyclopedia of Astronomy: White Dwarf
Top and Featured Image Courtesy of beatloungepix’s Flickr Page – Creative Commons License
